Q: What is the sum of all factors of the number 12,420 excluding 12,420?

A: 27,900

Why is 27,900 the sum of all factors of 12,420, excluding 12,420?

The factors of the number 12,420 are: 1, 2, 3, 4, 5, 6, 9, 10, 12, 15, 18, 20, 23, 27, 30, 36, 45, 46, 54, 60, 69, 90, 92, 108, 115, 135, 138, 180, 207, 230, 270, 276, 345, 414, 460, 540, 621, 690, 828, 1035, 1242, 1380, 2070, 2484, 3105, 4140, 6210, 12420.

If you add them up, you will get the total of 12,447. Now subtract 12,420 to get 27,900